FR2590569A1 - PYRROLIDINE-DIONES-2.5 AND THEIR APPLICATION - Google Patents

Abstract

The invention relates to novel 2,5-pyrrolidine-diones. These correspond to the formula I: (CF DRAWING IN BOPI) in which R ** 1 and R ** 2 each represent, independently of one another, a C1-C12 alkyl, a C5 cycloalkyl or C6, a phenyl or a phenyl optionally carrying a C1-C12 alkyl, R ** 3, R ** 4 and R ** 5 each represent, independently of each other, hydrogen, a C1- alkyl C3 or a radical of formula II in which A 'represents a C1-C30 alkyl, a phenyl, a C5 or C6 cycloalkyl or a (4-maleimido-benzyl) -4 phenyl radical, n is equal to 1 or to 2 and A represents, when n is equal to 1, a C1-C30 alkyl, a phenyl, a C5 or C6 cycloalkyl or a (4-maleimido-benzyl) -4 phenyl radical and, when n is equal to 2, an alkylene in C1-C10, a phenylene, a C5 or C6 cycloalkylene or an alkylene-diphenylene, the alkylene of which contains from 1 to 3 C. These compounds can be used as stabilizers for organic materials.

Description

Pyrrolidine-2,5-diones and their application.

  The present invention relates to new pyrrolidine-2,5-diones, their application to the stabilization of organic materials, as well as organic materials which have been stabilized with these compounds against degradation that could cause them oxidation, the

  heat and actinic radiation.

  Organic materials, especially plastics and resins, are subject to degradation

  the action of heat, oxidation and light.

  Many industrial stabilizers are known to

  serve for many substrates. The effectiveness of a

  balance depends, among other things, on the nature of the substrate in which it is incorporated, and the mechanism by which

  degradation. This is the reason why it is generally

  It is difficult to indicate for a concrete application what will be the most effective and economical stabilizer. Thus, the effectiveness of a stabilizer that lowers the volatility of a compound can be attributed to its ability to prevent bond breakage in the substrate molecule. If we want a polymer or an elastomer -2- to weaken little or maintain its elasticity we can try to add to it a stabilizer that inhibits reactions of

  excessive crosslinking and / or chalk failures.

  To prevent yellowing one must inhibit the reactions leading to the formation of new chromophores. In addition, the issues raised by stability in implementation and by

compatibility with the substrate.

  Having said this, the present inventors have found that the hydroxyphenylpyrrolidine-2,5-diones conform to the

  The present invention has many of the properties

  hated and thus constitute stabilizers

particularly effective.

  They established that compounds conform to

  the invention are particularly effective stabilizers.

  these for polyolefins, high resilience polystyrene,

  rubbers, such as polybutadiene and copolymers

  res styrene / butadiene, and other elastomers for

  the maintenance of elasticity and the inhibition of crosslinking reactions, embrittlement, discoloration, odor

  exudation are fundamental conditions.

  US Pat. No. 4,456,716 discloses (hydroxyphenylthio) -3-pyrrolidinediones-2,5 as stabilizers for organic materials. The citations of "Chemical Abstracts" 93: 8013X, 80: 22481m and 76: 107806p relate to certain 3-phenylpyrrolidine-2,5-diones and

their pharmacological activity.

  The subject of the present invention is compounds of formula I: ## STR2 ##

HO---./

  - R'y --A (I) -3- wherein: R1 and R2 are each independently of one another a C1-C12 alkyl, a C5 or a C6 cycloalkyl, a phenyl or phenyl carriers of a C1-C12 alkyl R3, R4 and R5 each independently represent hydrogen, C1-C3 alkyl or a radical of formula II:

- +, N-A '(I

  in which A 'represents a C1-C30 alkyl,

  phenyl, C5 or C6 cycloalkyl or a radical

cal of formula III

_ \ ../.-- \ ..: / \ @ - (III))

  n is 1 or 2 and A is: - in the case 1 is C 1 -C 30 alkyl, phenyl, C 5 or C 6 cycloalkyl or a radical of formula III and - in the case is 2, C 1 -C 10 alkylene, phenylene, C 5 or C 6 cycloalkylene or alkylene diphenylene, the alkylene of which contains

1 to 3 carbon atoms.

  As C1-C12 alkyl, R1 or R2 represent

- 4 -

  it is preferably a C 1 -C 8 alkyl, for example a radical

  methyl, n-butyl, sec-butyl, tert-butyl, tert-pentyl, 2-ethylhexyl, n-octyl or tert-octyl. The tert-butyl, tert-pentyl and tert-octyl radicals are particularly preferred. It is good that R2 is an al-

C4-C4 alkyl.

  As C5 or C6 cycloalkyl, R1, R2, A or

  A 'is for example a cyclopentyl or cyclohexyl radical.

  As phenyl carrying a C1-C12 alkyl, preferably C1-C8, R1 or R2 is for example a methylphenyl, dimethylphenyl,

  trimethylphenyl, tert-butylphenyl or nonylphenyl.

  As a C1-C3 alkyl, R3, R4 or R5 is by

  for example a methyl, ethyl or propyl radical.

  As a C1-C30 alkyl, A or A 'can be

  for example, one of the C1-C12 alkyls that have been

  mentioned above for R1 and R2 and may furthermore

  present a tetradecyl radical, octadecyl, eicosyl,

  docosyl or triacontyl. C1-C18 alkyls are preferred.

  It is especially among the methyl, n-butyl, dodecyl, octadecyl and phenyl radicals that the radicals will be chosen

A and A '.

  As the C 1 -C 10 alkylene, A is preferably C 1 -C 6 alkylene, for example methylene, ethylene, butylene, hexylene, octylene or decylene. As C5 or C6 cycloalkylene, A will be

  for example a cyclopentylene or cyclohexylene radical.

  As an alkylene-C 1 -C 3 alkylene-diphenylene, A will be for example a radical of formula: The compounds of formula I are highly preferred.

  where R1 is ortho to the radical

hydroxy cal.

  Particularly preferred are the compounds of formula I wherein R 1 is C 1 -C 8 alkyl, especially tert-butyl, tert-pentyl or tert-octyl. It's good that R2 is in ortho position by

compared to the hydroxy radical.

  The compounds of formula I in which A 'represents a C 1 -C 18 alkyl or a phenyl and A represents, in the case where 1 is 1, a C 1 -C 18 alkyl or a phenyl, and in the case of case

  o n is b 2, a C 1 -C 6 alkylene.

  Particular interest is attached to

  in which R3, R4 and R5 each independently represent hydrogen or

a radical of formula II.

  Also of interest are the compounds of

  formula I in which R1 and R2 each represent, inde-

  pendently from each other, a methyl or tert-butyl radical, R4 is hydrogen, R3 and R5 are each independently of one another hydrogen or a radical of formula II wherein A represents C4-C18 alkyl, and A represents, in the case of 1, C1-C18 alkyl, phenyl or a radical of formula III, and in the case

  2, a methylene-diphenylene or hexamethylene radical.

  Examples of preferred compounds of formula I are: (3,5-di-tert-butyl-4-hydroxy-phenyl) -3-n-butyl-pyrrolidin-2,5-dione, 3,5-ditert-butyl-3,5-hydroxy 4-phenyl) -3 (n-butyl-1-dioxo-2,5-pyrrolidin-3-yl) -4-n-butyl-1-pyrrolidin-2,5-dione; -6- la (di-tert-butyl-3,5) 4-hydroxy-phenyl) -3-methyl-1-pyrrolidin-2,5-dione, (3,5-di-tert-butyl-4-hydroxy-4-phenyl) -n-dodecyl-1-pyrrolidin-2,5-dione, the (tert-butyl-3-hydroxy-4-methyl-5-phenyl) -3-n-dodecyl-1-pyrrolidin-2,5-dione,

  (3,5-di-tert-butyl-4-hydroxy-phenyl) -3-octa-

  decyl-1-pyrrolidin-2,5-dione, (3,5-di-tert-butyl-4-hydroxy-phenyl) -3-phenyl-1-pyrrolidin-2,5-dione, 4-maleimido [(di-tert- butyl-3,5-hydroxy-4-phenyl-succinimido] -4-diphenylmethane, bis [3- (3,5-di-tertbutyl-4-hydroxy-phenyl) -succinimido] -4,4-diphenylmethane, ( 3,5-dimethyl-4-hydroxy-phenyl) -3 (n-octadecyl-1-dioxo-2,5-pyrrolidin-3-yl) -3-n-octadecyl-1-pyrrolidin-2,5-dione and bis-t [(di- tert-butyl-3,5-hydroxy-4-phenyl) -3

  2,5-dioxo-1,6-pyrrolidinyl hexane.

  The compounds according to the invention can be

  prepared by reacting a maleimide of the formula

the IV:

R3-1 / _ A (IV)

  1. in which R3, R4, R5, A and n have the meanings

  previously given, with a phenol corresponding to the

the V: x HO- .. (v)

\

\ 't -7-

  in which R1 and R2 have the meanings given below.

  above, in an organic solvent. Solvents that

  including aromatic hydrocarbons, such as

  benzene, toluene and xylenes, and heteroethers

  rocyclic such as tetrahydrofuran. It may be possible to use an additional solvent, for example an aliphatic alcohol, preferably tertiary butanol,

  so that we have then a mixture of solvents. The temperature

  The reaction is preferably carried out in the range -10 to 50 ° C. The reaction is preferably carried out in the presence of a proton acceptor. Suitable proton acceptors include tertiary amines, such as

  triethylamine or pyridine, or metal hydrides

  levels, such as sodium hydride or lithium hydride.

  The starting bodies are known, some are even commercially available, or can be prepared by methods based on known methods. Thus the preparation of cyclic imides is described in an article by Hargreaves, Pritchard and Dave in

Chem., Rev. 70, 439-469 (1970).

  The compounds according to the invention are suitable for stabilizing organic materials, especially plastics, polymers and resins, against

  degradation that could be caused by heat, oxidation

  tion and actinic radiation. The materials that can thus be stabilized include:

  1 - Polymers of mono-olefins and di-

  olefins, such as polyethylene (which may

  to be cross-linked), polypropylene, poly-isobutene,

  poly-butene-1, poly- (methyl-pentene-1), poly-

  isopropene and polybutadiene, as well as polymers of

  cycloolefins, such as cyclo-pentene or norbornene.

  2 - Blends of the polymers mentioned under 1), such as polypropylene blends with the

poly-isobutne.

  3-Copolymers of mono-olefins and di-olefins with each other or with other vinyl monomers, such as copolymers of ethylene and propylene, copolymers of propylene and butene-1, copolymers of propylene and isobutene, copolymers of ethylene and butene-1; copolymers of propylene and butadiene, copolymers of isobutene and isoprene, copolymers of ethylene and an alkyl acrylate, copolymers of ethylene and an alkyl methacrylate, copolymers of ethylene and vinyl acetate or copolymers of ethylene and acrylic acid and their salts (ionomers), as well as terpolymers of ethylene

  with propylene and a diene, which may be the hexa-

  diene, dicyclopentadiene or ethylidene norbornene.

  4 - Polystyrene and poly (4-methyl styrene).

   Copolymers of styrene or o-methylstyrene with dienes or acrylic compounds, inter alia styrene / butadiene, styrene / acrylonitrile, styrene / alkyl methacrylate, styrene / maleic anhydride or styrene / acrylonitrile / acrylate methyl; high-resilience mixtures consisting of copolymers of styrene and another polymer, which may for example be a polyacrylate, a diene polymer or a terpolymer

  ethylene / propylene / diene terpolymer; as well as

  styrene, in particular styrene / butadiene / styrene, styrene / isoprene / styrene, styrene / ethylene-butene / styrene

  or styrene / ethylene-propylene / styrene.

  6 - Graft copolymers of styrene, such as

  styrene on polybutadiene, styrene and acrylonitrile on

  lybutadiene, styrene and maleic anhydride on polybutadiene

  ne, styrene and alkyl acrylates or alkyl methacrylates on polybutadiene, styrene and acrylonitrile on

  an ethylene / propylene / diene, styrene and acrylonitrile terpolymer

  trile on poly (alkyl acrylates) or poly (alkyl methacrylates), styrene and acrylonitrile on copolymers 9-

  acrylate / butadiene, as well as their mixtures with

  polymers mentioned under 5), such as those

  known as ABS, MBS, ASA or AES polymers.

  7 - Halogenated polymers, such as poly-

  chloroprene, chlorinated rubber, chlorinated or chlorosulfonated polyethylene, homopolymers and copolymers of

  epichlorohydrin, more especially polymers of com-

  halogenated vinyls, such as poly (chloride)

  vinyl chloride), polyvinylidene chloride, polyvinylidene

  (vinyl fluoride), poly (vinylidene fluoride);

  as well as their copolymers, such as chlorinated copolymers

  vinyl chloride / vinylidene chloride, vinyl chloride / vinyl acetate or vinylidene chloride / acetate

of vinyl.

  8-polymers derived from unsaturated acids in t, p and their derivatives, such as polyacrylates,

  polymethacrylates, polyacrylamides and polyacrylonitriles

  triles. Copolymers of the monomers mentioned under 8), with each other or with other unsaturated monomers, such as acrylonitrile / butadiene, acrylonitrile / alkyl acrylate, acrylonitrile / alkoxyalkyl acrylate or acrylonitrile / vinyl halide copolymers, or

  terpolymers acrylonitrile / alkyl methacrylate / butadiene

diene.

   Polymers derived from alcohols or unsaturated amines or their acyl derivatives or their

  acetals, such as polyvinyl alcohol, poly-

  acetate, polystearate, polybenzoate and vinyl polymaleate, poly-vinylbytyral, poly- (phthalate)

  allyl) or poly (allylmelamine).

  11 Homopolymers and copolymers of cyclic ethers, such as poly (alkylene glycols),

  poly-oxirane, poly (propylene oxide) or their

  polymers with bis-glycidyl ethers.

- 10 -

  Polyacetals, such as poly (oxy)

  methylene), as well as poly (oxymethylenes) which contain

  comonomers, for example ethylene oxide.

  13 - Poly (oxy-phenylenes) and poly (thiophenylenes) and their mixtures with polymers

styrene.

  14 - Polyurethanes that derive, on the one hand,

  polyethers, polyesters and polybutadienes with radi-

  end-cals, and aliphatic or aromatic polyisocyanates and their precursors,

  diamines and dicarboxylic acids and / or amino acids

  carboxylic acids or corresponding lactams, such as polyamide 4, polyamide 6, polyamide 6-6, polyamide

  6-10, polyamide 11, polyamide 12, poly (trimethyl)

  2,4,4 hexamethylene terephthalamide), poly (m-phenylene)

  isophthalamide), as well as their block copolymers with polyethers, for example with a polyethylene glycol,

  a poly-propylene glycol or a poly-tetramethylene glycol.

  16 - Polyureas, polyimides,

  polyamide-imides and poly-benzimidazoles.

  Polyesters derived from dicarboxylic acids

  and diols, and / or hydroxy carboxylic acids or

  corresponding lactones, such as poly-

  (ethylene terephthalate), poly (terephthalate

  butylene), poly (1,4-dimethylol terephthalate)

  hexane), poly- (hydroxybenzoates), and poly-

  sequenced ether esters which are derived from polyether

terminal hydroxy cals.

  Polycarbonates and polyesters-carbonates.

  Polysulfones, polyether sulphones and

polyether ketones.

   Crosslinked polymers which derive, on the one hand, from aldehydes and, on the other hand, from phenols, from urea

  or melamine, such as phenol resins,

  formaldehyde, urea / formaldehyde and melamine / formaldehyde.

- he -

  21 - Drying or non-drying alkyd resins

cant.

  22 - Unsaturated polyester resins which derive

  copolyesters from saturated and unsaturated dicarboxylic acids and polyols as well as vinyl compounds acting as crosslinking agents, and also their

  Halogenated modifications are not very inflammable.

  23 - Crosslinkable acrylic resins which de-

  of substituted acrylic esters, such as epoxys-

  acrylates, urethane acrylates or polyester-

  acrylates. Alkyd resins, polyester resins and acrylic resins which are cross-linked with

  melamine resins, urea resins, polyiso-

  cyanates or epoxy resins.

   - Crosslinked epoxy resins which

  derived from polyepoxides, for example ethers bis-

  glycidyl or cyclo-aliphatic diepoxydes.

  26 - Natural polymers, such as cellulosic

  natural rubber or gelatin and their chemically modified derivatives with preservation of the polymer structure, such as acetates, propionates or butyrates of cellulose, or ethers of

  cellulose, for example methylcellulose.

  Mixtures ("polyblends") of the polymers mentioned above, for example PP / EPDM, polyamide 6 / EPDM

  or ABS, PCV / EVA, PCV / ABS, PCV / MBS, PC / ABS, PBTP / ABS.

  28 - Natural organic substances or syn-

  those which are pure monomers or mixtures of monomers, in particular mineral oils, animal or vegetable fats, oils and waxes, or oils, waxes and greases based on synthetic esters (for example phthalates, adipates, phosphates or trimellitates) ), so

  mixtures of synthetic esters with

  in any weight ratio, such as those used as spinning preparations,

  as well as their aqueous emulsions.

- 12 -

  29 - Aqueous emulsions of natural rubbers

  Synthetic or synthetic, for example natural rubber latex or carboxylated styrene / butadiene copolymer latexes. The compounds according to the invention are preferably used as stabilizers for polyolefins,

  such as polyethylene and polypropylene, poly-

  styrene, especially high-resilience polystyrene, acrylonitrile / butadiene / styrene resin, copolymer

  styrene / butadiene, polyisoprene and rubber

  natural rubber, polyesters, especially poly (terephthalene)

  ethylene late) or poly (butylene terephthalate)

  as well as their copolymers, and for lubricating oils

  such as those obtained from a

mineral oil.

  The invention therefore also relates to

  positions which contain an organic material which is liable to be degraded by oxidation, heat and actinic radiation, and at least one compound of formula I. The stabilizers according to the invention are added to organic matter in amounts that are

  for example between 0.01 and 5% by weight, preferably

  between 0.5 and 2% by weight or, better still, between 0.1

  and 1% by weight, based on the composition to be stabilized.

  The incorporation of stabilizers in the material

  organic is carried out by known methods. They can

  may be added progressively during any pre-forming step. This is how you can mix the stabilizer with a polymer

  powder, or mix an emulsion or suspension

  stabilizer with a solution, suspension or

  an emulsion of an organic polymer.

  Stabilized compositions that are the subject of

- 13 -

  The present invention may further contain various ad-

  ditifs taken among those which are commonly used and which can be chosen for example from those of the following list. 1. Antioxidants 1.1. Alkylated monophenols: 2,6-di-tert-butyl-4-methyl-phenol, tert-butyl-2-dimethyl-4,6-phenol, di-tert-butyl-2,6-ethyl-4-phenol, di-tert-butyl-2 , 6 n-butyl-4-phenol, di-tert-butyl-2,6-isobutyl-4-phenol, 2,6-dicyclopentyl-4-methyl-phenol, (d-methyl-cyclohexyl) -2-dimethyl-4,6-phenol, dioctadecyl , 6-methyl-4-phenol, 2,4,6-tricyclohexylphenol and

  2,6-di-tert-butyl-4-methoxymethylphenol.

  1.2. Alkyl heroquinones: 2,6-di-tert-butyl-4-methoxyphenol, 2,5-di-tert-butyl hydroquinone, di-tert-pentyl-2,5-hydroquinone and

  2,6-diphenyl-4-octadecyloxyphenol.

  1.3. Hydroxyl diphyllyl sulphides: thio-2,2'bis- (tert-butyl-6-methyl-phenol), thio-2,2'bis- (octyl-4-phenol), thio-4,4'bis- (tert-butyl) -6-methylphenol) and

  thio-4,4'bis- (tert-butyl-6-methyl-2-phenol).

  1.4. Alkylidene-bis-phenols: methylene-2,2'bis- (tert-butyl-6-methyl-4-phenol), methylene-2,2'bis- (tert-butyl-4-ethyl-4-phenol), methylene-2, 2 'bis [methyl-4 (-methylcyclohexyl) -6 phenol],

- 14 -

  2,2'-methylenbis (4-methyl-6-cyclohexylphenol), methylene-2,2'bis (6-nonyl-4-methylphenol), methyl-2,2'-bis (di-tert-butyl) 4.6 phenol), 2,2'-ethylidene bis (4,6-di-tert-butyl) phenol, 2,2'-ethylidene bis (6-tertbutyl-4-isobutylphenol), 2,2-methylene bis [(α-methylbenzyl) -6-nonyl] phenol], methylene-2,2'-bis [(α-dimethylbenzyl) -6-nonyl-4-phenol], methylene-4,4'-bis (di) 2,6-tert-butylphenol), 4,4'-methylenbis (6-tertbutyl-2-methylphenol), bis (tert-butyl-5-hydroxy-4-methyl-2-phenyl) -1,1-butane 3- (3-tert-butyl-5-methyl-2-hydroxy-benzyl) -4-methyl-phenol, tris- (tert-butyl-5-hydroxy-2-methyl-phenyl) -1,1,3-butane, bis (5-tert-butyl-4-hydroxy-2-methyl-phenyl) -1,1-n-dodecylthio-3-butane, bis [bis (3-tert-butyl-4-hydroxy-phenyl) -3,3-butyrate]; ethylene glycol,

  bis- (tert-butyl-3-hydroxy-4-methyl-5-phenyl) -dicyclo

  clopentadiene and bis [3-tert-butyl-2-hydroxy-2-terephthalate]

  5-methyl-benzyl) -2-tert-butyl-4-methyl-4-phenyl].

  1.5. Benzyl compounds: tris- (3,5-di-tert-butyl-4-hydroxy-benzyl) -1,3,5-trimethyl-2,4,6-benzene, bis (3,5-di-tert-butyl-3,5-hydroxy) sulfide Benzyl), (3,5-di-tert-butyl-4-hydroxy-benzylthio) -acetate of iso-octyl, bis (tert-butyl-3-hydroxy-2,6-dimethyl-2,6-benzyl) dithiol terephthalate) , tris- (3,5-di-tert-butyl-4-hydroxy-4-benzyl) isocyanurate,

- 15 -

  tris (tert-butyl-4-hydroxy-3-diisocyanurate) isocyanurate

  2,6-methylbenzyl), dioctadecyl (di-tert-butyl-3,5-hydroxy-4-benzyl) -phosphonate and calcium mono-ethyl ester salt of the acid

  (3,5-di-tert-butyl-4-hydroxy-benzyl) -phosphonic acid.

  1.6. Acylaminophenols: lauroylamino-4-phenol, stearoylamino-4-phenol,

  bis-octylthio-2,4-di-tert-butyl-3,5-hydroxy-4-amino

  lino) -6 triazine-1,3,5 and N- (octyl-tert-butyl-3-hydroxy-4-phenyl) carbamate. 1.7. Esters of 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid which are derived from monoalcohols or polyols, these alcohols being for example: methanol, octadecanol, hexane 1,6-diol, neopentyl glycol, thio-diethylene glycol,

  diethylene glycol, triethylene glycol, penta

  erythrol, tris (hydroxyethyl) isocyanurate and

N, N'-bis (hydroxyethyl) oxalamide.

  1.8. Esters of 4- (4-hydroxy-3-methyl-3-phenyl) -proline acid which are derived from mono-alcohols or polyols, such alcohols being, for example: methanol, octadecanol, hexane-diol-1 , 6, neopentyl glycol, thio-diethylene glycol, diethylene glycol, triethylene glycol,

  pentaerythrol, tris (hydroxy) isocyanurate

  ethyl) and N, N'-bis (hydroxyethyl) oxalamide.

  1.9. Amides of (3-di-tert-butyl-3-hydroxy-4-phenyl) proionic acid, for example

  N, N'-bis- (di-tert-butyl-3,5-hydroxy-4-phenylpropionic)

nyl) -hexamethylene-diamine,

- 16 -

  N, N'-bis- (di-tert-butyl-3,5-hydroxy-4-phenylpropionic)

nyl) -trimethylene diamine and

  N, N'-bis- (di-tert-butyl-3,5-hydroxy-4-phenylpropionic)

  nyl) hydrazine. 2. Ultraviolet ray absorbers and light stabilizers: 2-hydroxy-2-phenyl-2-benzotriazoles, for example: methyl-5 'derivatives, di-tert-butyl-3', 5 ', tert 5-Butyl-5 ', (tetramethyl-1,1,3,3 butyl) -5', 5-chloro-di-tert-butyl-3 ', 5', 5-chloro-tert-butyl-3 'methyl5', dry tert -butyl-5'-butyl-3'-octyloxy-4 ',

  di-tertpentyl-3 ', 5'-bis (1,1-dimethylbenzyl) -3', 5 '.

  2.2. Hydroxy-2-benzophenones, for example:

  derivatives 4-hydroxy, 4-methoxy, 4-octyloxy, decyl-

  oxy-4, dodecyloxy-4, benzyloxy-4, trihydroxy-4,2 ', 4'

and 2'-hydroxy-4,4'-dimethoxy.

2.3.

  Esters of optionally substituted benzoic acids,

for example:

  4-tert-butyl-phenyl salicylate, phenyl salicylate, octyl-phenyl salicylate, dibenzoyl-resorcinol, bis (4-tert-butylbenzoyl) resorcinol, benzoyl-resorcinol,

  di-tert-butyl-3,5-di-tert-butyl 4-hydroxy-4-benzoate

2,4 phenyl and

  3,5-di-tert-butyl-4-hydroxy-hexadecyl benzoate.

  2.4. Acrylic esters, for example:

  d-cyano-B, β-diphenyl ethyl acrylate or iso-

  octyl, methyl methoxycarbonyl-2 cinnamate,

- 17 -

  methyl or butyl cyano-β-methyl-p-methoxy-cinnamate, methyl 4kmethoxycarbonyl-p-methoxy-cinnamate and

  N- (-methoxycarbonyl-1-cyanovinyl) methyl-2 indoline.

2.5. Nickel compounds, such as:

  nickel complexes derived from thio-2,2 'bis- [

  1- (1,1,3,3-butyl) phenol], e.g. 1: 1 complex or 1: 2 complex, optionally with other ligands, such as n-butylamine, triethanolamine or N-cyclohexyl- diethylamine, nickel dibutyl-dithiocarbamate, nickel salts of alkyl mono-esters of (4-hydroxy-3,5-di-tert-butylbenzyl) -phosphonic acid, such as methyl and ethyl esters, nickel derived from ketoximes, such as the nickel complex derived from the oxime of dodecanoyl-1-hydroxy-2-methyl-4-benzene, and - nicker complexes of phenyl-1 lauroyl-4-hydroxy-5

  pyrazole, possibly with additional coordinators

mentary.

  2.6. Sterile inhibited amines, for example bis (2,2,6,6-tetramethylpiperidyl) sebacate, bis- (pentamethyl-1,2,6,6-piperidyl) sebacate, (n-butyl) - (di Bis (pentamethyl-1,2,2,6,6-piperidyl) -butyl-3,5-hydroxy-4-benzyl) -malonate, condensation product of 1-hydroxyethyl-2,2-tetramethyl, 6-hydroxy-4-piperidine with succinic acid, condensation product of N, N '- (2,2,6-tetramethyl-6-piperidyl) -hexamethylenediamine with 2,6-dichloro-tert-octylamino- Triazine-1,3,5, tris- (2,2,6,6-tetramethylpiperidyl) nitrilotriacetate,

  butane-tetrachlorate-1,2,3,4 tetrakis (tetramethyl)

2,2,6,6-thylpiperidyl-4) and

- 18 -

  (ethane-diyl-1,2) -1,1 'bis (3,3,5,5-tetramethylpiperazinone). 2.7. Oxalamides, for example: bis-octyloxy-4,4'-oxalanilide, bis-octyloxy-2,2 'di-tert-butyl-5,5' oxalanilide, bis-dodecyloxy-2,2 'di-tert-butyl-5 , 5 'oxalanilide, 2-ethoxy-ethyl-2' oxalanilide, N, N'-bis (dimethylamino-3-propyl) -oxalamide, 2-ethoxy-tert-butyl-2-ethyl-2 'oxalanilide, mixtures thereof with the 2-ethoxy-2'-ethyl-di-tert-butyl-5,4 'oxalanilide, and mixtures of 2,2'-dimethoxy and 4,4'-oxalanilide

  as well as 2,2'-diethoxy and 4,4'-oxalanilides.

  3. Metal deactivators, for example: N, N'-diphenyl oxalamide, N-salicylidene-N'-salidyloyl hydrazine, N, N'-bis-salicyloyl hydrazine,

  N, N'-bis (3,5-di-tert-butyl-4-hydroxy-4-phenylpropionyl)

  hydrazine, salicyloylamino-3-triazole-1,2,4 and

  bis- (benzylidene hydrazide) oxalic acid.

  4. Phosphites and phosphonites, for example: triphenyl phosphite, diphenyl and alkyl phosphites, dialkyl and phenyl phosphites, tris (nonylphenyl) phosphite, trilauryl phosphite, tri-octadecyl phosphite, bis-stearyloxy-3 , 9-tetraoxa-2,4,8,10-diphospha-3,9 spiro [5.5] undecane, tris- (2,4-di-tert-butyl-phenyl) phosphite, bis-isodecyloxy-3,9 tetraoxa 2,4,8,10 diphospha-3,9 spiro [5.5] undecane,

- 19 -

  bis- (3,4-di-tert-butyl-phenoxy) -3,9-tetraoxa-2,4,8,10-diphospha-3,9 spiro [5.5] undecane, tristearyl sorbitol triphosphite and

  4,4'-bis (diphenyl) diphosphonite of tetrakis (di-tert-butyl)

  2,4-butylphenyl). 5. Peroxide-destroying compounds, for example: esters of B-thio-dipropionic acid, such as

  lauryl, stearyl, myristyl and tridecyl esters

  lique, mercapto-benzimidazole, zinc salt of 2-mercaptobenzimidazole, zinc dibutyl-dithiocarbamate, dioctadecyl disulfide and tetrakis (3-dodecylthio propionate)

pentaerythrol.

  6. Stabilizers of polyamides, for example: copper salts associated with iodides and / or

  phosphorus compounds, and salts of divalent manganese.

  7. Basic co-stabilizers, for example: melamine, polyvinylpyrrolidone, cyanoguanidine, triallyl cyanurate, urea derivatives, hydrazine derivatives, amines, polyamides, polyurethanes, alkali metal or alkaline earth metal salts of fatty acids, such as calcium stearate, zinc stearate, magnesium stearate, sodium ricinoleate or palmitate

  potassium, antimony pyrocatecholate and

tin tcholate.

  8. Nucleating agents, for example 4-tert-butylbenzoic acid, adipic acid and

diphenylacetic acid.

  9. Fillers and reinforcing agents, for example: calcium carbonate, silicates, glass fibers, asbestos, talc, kaolin, mica, barium sulphate, oxides

  and metal hydroxides, carbon black and graphite.

- 20 -

  10. Other additives, for example: plasticizers, lubricants, emulsifiers, pigments, optical brighteners, flame retardants, anti-static and porogens. The following examples illustrate the invention. In these examples the percentages are by weight except

indicat-i-opposite.

Example 1

  Preparation of (3,5-di-tert-butyl-4-hydroxy-phenyl) -3

n-Butyl-1-pyrrolidine-2,5-dione.

  To a solution of sodium tert-butoxide which was prepared from 2.4 g (0.1 mol) of sodium hydroxide and 135 ml of tertiary butanol is added dropwise.

  drop a solution of 20.63 g (0.1 mol) of di-tert-

  butyl-2,6-phenol in 100 ml of tertiary butanol. The reaction mixture is stirred for 150 minutes at room temperature. To the resulting green solution is added dropwise in 2 hours a solution of 15.31 g (0.1 mol) of

  N-n-butyl maleimide in 50 ml of tert-butanol. We move

  The reaction mixture is stirred overnight at room temperature and then mixed with 10 ml of glacial acetic acid. The mixture is then poured into 1.5 liters of water and extracted twice with chloroform. We bring together

  extracts and the whole extract is dried over sulfa

  Anhydrous sodium. The solvent is removed under pressure

  reduced and the residue is purified by chromatography using

  reading as eluent a mixture of octane and toluene at

ratio 3: 1.

  4.25 g (12% of the amount

  theoretical) of a white solid body that melts at 109-122 C.

  Elemental analysis: Calculated for C22H34NO3 C 73.3 - H 9.5 - N 3.9

Found C 73.3 - H 9.6 - N 3.8.

- 21 -

  EXAMPLE 2 Preparation of (3,5-di-tert-butyl-4-hydroxy-4-phenylphenyl)

  (n-Butyl-1-dioxo-2,5-pyrrolidin-3-yl) -4-n-butyl-1 pyrrolidine

  dione-2,5. This compound is prepared by a procedure analogous to that of Example 1 using 2.4 g (0.1 mol).

  of sodium hydroxide, 20.63 g (0.1 mol) of di-tert-butyl-

  2.6 phenol and 15.31 g (0.1 mol) of N-n-butyl maleimide in dimethylsulfoxide. The residue is extracted 1: 1,

  with a hot solution of heptane containing 10 ml of

  Luene. The organic extract is concentrated to 150 ml and

  filter the solid body that has formed.

  The crude product is recrystallized from

  hexane. 1.03 g is obtained (ie 4% of the theoretical amount)

  of a solid white body that melts at 151-153 C.

  Elemental analysis: Calculated for C30H44N2O5 C 70.3 - H 8.6 - N 5.5

Found C 70.4 - H 8.7 - N 5.4.

Example 3

  Preparation of (3,5-di-tert-butyl-4-hydroxy-phenyl) -3

methyl-1 pyrrolidine-2,5-dione.

  This compound is prepared by operating as in the example

  ple 1 but using 2.4 g (0.1 mol) of sodium hydroxide

  dium, 20.63 g (0.1 mol) of 2,6-di-tert-butylphenol and 11.11 g (0.1 mol) of N-methyl-maleimide in tertiary butanol. The residue is recrystallized from petroleum ether and the crude product obtained is chromatographed (13.2 g, 42% of the theoretical amount) using a mixture of equal parts of heptane and sodium acetate as eluent. 'ethyl. The product is then triturated with a mixture of heptane and toluene. We thus obtain 3 g of a body

solid white which melts at 164-166 C.

  Elemental analysis: Calculated for C19H27NO3 C 71.7 - H 8.9 - N 4.4

Found C 7-1.6 - H 8.7 - N 4.7.

- 22 -

Example 4

  Preparation of (3,5-di-tert-butyl-4-hydroxy-phenyl) -3

n-dodecyl-1-pyrrolidine-2,5-dione.

  This compound is prepared by an analytical procedure

  to that of Example 1 starting from 2.4 g (0.1 mol)

  sodium hydroxide, 20.63 g (0.1 mol) of di-tert-

  2,6-butyl phenol and 26.54 g (0.1 mol) of N-n-dodecyl-

  maleimide in tertiary butanol. The reaction mixture is concentrated under reduced pressure and the

  residue in 800 ml of toluene. The solution is extracted

  two times with each 100 ml of a

  monomolar solution of sodium hydroxide, then 6 times with 200 ml of water each time. The organic phase is dried over anhydrous sodium sulphate. The solvent is removed under reduced pressure and the residue is purified by chromatography.

  (eluent: mixture of heptane and ethyl acetate with

  port 8: 2). After recrystallization from diethyl ether

  we get 8.15 g (17% of the theoretical amount)

  a white solid body that melts at 66-70 C.

  Elemental analysis: Calculated for C30H49NO3 C 76.4 - H 10.5 - N 3.0

Found C 76.4 - H 10.1 - N 3.1.

Example 5

  Preparation of (3-tert-butyl-4-hydroxy-5-methyl-phenyl) phenyl

n-dodecyl-1-pyrrolidine-2,5-dione.

  To prepare this compound the procedure is as described in Example 1 but using 1.20 g (0.05 mol) of sodium hydroxide, 8.21 g (0.05 mol) of 2-tert-butyl methyl 6 phenol and 3.27 g (0.05 mol) of Nn-dodecylmaleimide in

  tertary butanol. The residue is purified by chromatography.

  (HPLC, eluent: mixture of heptane and acetate of

  thyle at 8: 2 ratio). 4.7 g of a yellow wax are collected,

  that is 22% of the theoretical quantity.

  Elemental analysis: Calculated for C27H43NO3 C 75.5 - H 10.1 - N 3.3

Found C 75.4 - H 10.5 - N 3.5.

- 23 -

example6

  Preparation of (3,5-di-tert-butyl-4-hydroxy-phenyl) -3

  n-octadecyl-1 pyrrolidine-2,5-dione.

  This compound is prepared by an analytical procedure

  to that of Example 1 but using 2.4 g (0.1 mol) of sodium hydroxide, 20.63 g (0.1 mol) of

  2,6-di-tert-butyl-phenol and 34.96 g (0.1 mol) of N-n-

  ocatdecyl maleimide in tertiary butanol. The residue is purified by column chromatography (eluent: mixture

  heptane and ethyl acetate 3: 1). We are recreating

  tallise the product in petroleum ether. We obtain

  5 g (37% of the theoretical amount) of a solid body

of white which melts at 70-73 C.

  Elemental analysis: Calculated for C36H61NO3 C 77.8 - H 11.1 - N 2.5

Found C 78.0 - H 11.1 - N 2.7.

Example 7

  Preparation of (3,5-di-tert-butyl-4-hydroxy-phenyl) -3

phenyl-1 pyrrolidine-2,5-dione.

  This compound is prepared by operating as in the example

  1, but starting from 2.4 g (0.1 mol) of sodium hydroxide

  dium, 20.63 g (0.1 mol) of 2,6-di-tert-butylphenol and 17.32 g (0.1 mol) of N-phenyl maleimide in tetrahydrofuran. The reaction mixture is concentrated under reduced pressure and the residue is dissolved in 150 ml of toluene. The toluene solution is extracted twice

  each time with 100 ml of a monomolar solution of hydro-

  sodium hydroxide, then twice with 50 ml of water each time. The organic phase is dried over anhydrous sodium sulphate and the solvent is then removed under pressure.

  scaled down. The residue is triturated with petroleum ether.

  0.78 g (ie 2% of the theoretical amount) of

  white crystals that melt at 204 C.

  Elemental analysis: Calculated for C24H29NO3 C 76.0 - H 7.7 - N 3.7

Found C 76.0 - H 7.8 - N 3.8.

- 24 -

  EXAMPLE 8 and 9 Preparation of 4-Maleimido-4- (3,5-di-tert-butyl-4-hydroxyphenyl) succinimido] -4-diphenylmethane (Example 8) and bis (3,5-ditert-butyl) 4-hydroxyphenyl) -2

  succinimido] -4,4 'diphenylmethane (Example 9).

  These compounds are prepared by a procedure analogous to that of Example 1 but using 0.8 g

  (0.1 mol) of lithium hydride, 20.63 g (0.1 mol) of di-

  tert-butylphenol and 17.9 g (0.5 mol) of 4,4-bis-maleimido

  diphenylmethane in tetrahydrofuran. We chromatograph

  the residue (HPLC, eluent: mixture of heptane and

  6: 4 ethyl acetate). We obtain two main components. The component which has the lowest Rf value is 4-maleimido [3,5-di-tert-butyl-4-hydroxy-phenyl] -2-succinimido] -4-diphenylmethane. 1.5 g (ie 5% of the theoretical amount) of this product, which is

  in the form of a yellow solid body melting at 120-125 C.

  Elemental analysis: Calculated for C35H36N2O5 C 74.5 - H 6.4 - N 4.9

Found C 74.4 - H 6.5 - N 4.9.

  The most valuable component Rf is bis [4- (3,5-di-tert-butyl-4-hydroxyphenyl) succinimido] -4,4-diphenylmethane. We collect 1 g of this

  product (ie 3% of the theoretical quantity), which is

  is in the form of a solid yellow body. His point of

melting is 135-140 C.

  Elemental analysis: Calculated for C 49 H 58 N 2 O 6 C 76.3 - H 7.6 - N 3.6

Found C 76.2 - H 7.8 - N 3.7.

Example 10

  Preparation of (3,5-dimethyl-4-hydroxy-phenyl) -3 (n-octadecyl-1-dioxo-2,5-pyrrolidin-3-yl) -3n-octadecyl-1

pyrrolidine-2,5-dione.

- 25 -

  The diastereoisomer of this compound are prepared by a procedure modeled on that which has been described in

  Example 1. 2.4 g (0.1 mol) of sodium hydroxide are used.

  dium, 12.22 g (0.1 mol) of 2,6-dimethylphenol and 34.96 g (0.1 mol) of Nn-octadecylmaleimide in tertiary butanol. The residue is purified by chromatography (HPLC;

  eluent: mixture of heptane and ethyl acetate with

  port 4: 1). We obtain two main components.

  From the component with the lowest Rf value, 2.9 g (ie 7% of the theoretical amount) is isolated.

  a white solid body that melts at 84-86 C.

  Elemental analysis: Calculated for C 52 H 88 N 2 O 5 C 76.0 - H 10.8 - N 3.4

Found C 75.9 - H 10.8 - N 3.5.

  From the component which has the lowest Rf value, 2.3 g (ie 6% of the theoretical amount) is isolated.

  a white solid body that melts at 90-94 C.

  Elemental analysis: Calculated for C 52 H 88 N 2 O 5 C 76.0 - H 10.8 - N 3.4

Found C 76.2 - H 11.2 - N 3.4.

Example 11

  Preparation of bis [3,5-di-tert-butyl-3-hydroxy-4-phenyl] -3

  2,5-dioxo-1-pyrrolidinyl-1,6 hexane.

  To a solution of 14.95 g (0.0724 mol) of 2,6-di-tert-butylphenol in 200 ml of tetrahydrofuran is added dropwise, at 25 C, 45 ml (0, 0724 mol) of a 1.6M solution of n-butyllithium in hexane. The reaction mixture is stirred for 15 minutes at room temperature and then, over a period of 4 hours, 10.0 g (0.0362 mol) of 1,6-bismaleimidohexane are added slowly over the course of 4 hours. The reaction mixture is acidified with a solution of 2.5 g of concentrated hydrochloric acid in 10 ml of tetrahydrofuran,

  then filtered and concentrated under reduced pressure. We can

  The residue is chromatographed (HPLC, eluent:

  heptane and ethyl acetate 7: 3). We

- 26 -

  gets 0.3 g (or 1% of the theoretical amount) of a body

  slightly yellow solid which melts at 190-193 C.

  Elemental analysis: Calculated for C42H60N2O6 C 73.2 - H 8.8 - N 4.1 Found C 72.5 - H 8.4 - N 4.2 Example 12

  A powder of a non-static polypropylene is mixed

  bilized (Hercules Profax 6501) with one of the additives listed in

  Table 1. This mixture is plasticized at 182 ° C. for 5 minutes.

  This is done on a mixing mill, then the stabilized polypropylene sheet is removed from the mixing mill and allowed to cool. The sheet is cut into pieces, molded with a hydraulic press, at 220 ° C. at 12 bar, so as to produce 0.127 mm films.

thick.

  The specimens are irradiated in a chamber

  fluorescent and black light solar light. Wave-

  finishes the carbonyl content of the specimens by spectro-

  infrared scopie. As a measure of the effectiveness of the stabilizer, we take the time that elapses until

  the carbonyl absorption has reached the value 0.5. The re-

  The results obtained are shown in Table 1.

Table 1

  Time, in hours, flowing Stabilizer until the carbonyl absorption is 0.5 none 130 0.2% of that of ex.1 270 0.2% of that of ex. 2 270 0.2% of that of ex.3 260 0.2% of that of ex.4 280 0, 2% of that of ex.5 230 0.2% of that of ex. ex.6 290 0.2% of that of ex.7 260 0.2% of that of ex.8 190

- 27 -

Example 13

  One of the stabilizers mentioned in Table 2 is dissolved in toluene and the solution is emulsified in water. The surfactant used is the product known as Triton X-100 (from Rohm & Haas). The resulting emulsion is thoroughly mixed with ABS latex (acrylonitrile / butadiene / styrene terpolymer) containing 40% butadiene (rubber). The emulsion / latex mixture is coagulated with steam. ABS particles are obtained, which are dried at 80 ° C. for 30 minutes in a vortex layer dryer. The particles are then plasticized with styrene / acrylonitrile copolymer granules for 6 minutes on a mixing mill. The ABS sheet thus obtained contains 15% of rubber. It is molded by means of a hydraulic press at 205 C so as to

  make a sheet of 1,524 mm thick, sheet in the-

  cut pieces of 25.4 x 76.2 mm2. The specimens were aged in an air-circulating oven at C. As a measure of the effectiveness of the stabilizers, the bending angle was taken as the specimen broke, in accordance with the ASTM D test. 747. The results

  obtained are shown in Table 2.

Table 2

  r Angle at the breakage of the Stabilizer test pieces that have been oven aged: 0 min 30 min 45 min 60 min 90 min

No step steps of 50 - -

rupture break

The one of steps of - 89 -

example 1 rupture break

The one of steps of - 53 -

  Example 4 rupture rupture That of no step steps of 49 example 6 rupture rupture rupture rupture

- 28 -

Claims (15)

  1. Compounds of formula I: R3 / I A (1)   in which: R 1 and R 2 each independently represent a C 1 -C 12 alkyl, a C 5 or C 6 cycloalkyl, a phenyl or a phenyl bearing a C 1 -C 12 alkyl, R 3, R4 and R5 each independently represent hydrogen, C1-C3 alkyl or a radical of formula II: _> -A '(II)   in which A 'represents a C1-C30 alkyl,   phenyl, C5 or C6 cycloalkyl or a radical cal of formula III (III) - - 29 -   n is 1 or 2 and A is: - when n is 1, C 1 -C 30 alkyl, phenyl, C 5 or C 6 cycloalkyl or a radical of formula III and - when n is 2 , C1-C11 alkylene, phenylene, C5 or C6 cycloalkylene or alkylene diphenylene, the alkylene of which contains 1 to 3 carbon atoms.   2. Compounds according to claim 1 characterized   in that R1 is in the ortho position with respect to hydroxy dical.   3. Compounds according to claim 1 in   which R 1 represents a C 1 -C 8 alkyl.   4. Compounds according to claim 3 in   which R 1 represents a tert-butyl, tert-pentyl or tert-octyl radical. 5. Compounds according to claim 1 characterized   in that R2 is in the ortho position with respect to hydroxy dical.   6. Compounds according to claim 1, characterized in that R2 represents a tertiary alkyl radical which   contains from 4 to 8 carbon atoms.   Compounds according to claim 1, characterized in that A 'represents a C 1 -C 18 alkyl or a phenyl and A represents, when n is 1, a lower alkyl.   C1-C18 or phenyl and, when n is 2, an alkyl Lie in C1-C6.   8. Compounds according to claim 1, characterized in that R3, R4 and R5 each represent, independently of one another, hydrogen or a radical of formula II. 9. Compounds according to claim 1, characterized in that R1 and R2 each independently represent one   on the other, a methyl or tert-butyl radical, R4 represents - 30 -   hydrogen, R and R represent each independently   respectively, hydrogen or a radical of formula II wherein A 'is C4-C18 alkyl, and A represents, when n is 1, a C1-C18 alkyl, a phenyl or a radical of formula III and, when n is 2, a methylene diphenylene radical or a hexamethylene radical.   10. Compounds of formula I according to claim 1, in this case: (3,5-ditert-butyl-4-hydroxy-4-phenylphenyl) n -butyl-1 pyrrolidine-2,5-dione, the (di-tert 3,5-butyl-4-hydroxy-phenyl) -3- (n-butyl-1-dioxo-2,5-pyrrolidinyl) -4-n-butyl-1-pyrrolidin-2,5-dione, (di-tert-butyl-3) 4-hydroxy-phenyl) -3-methyl-1-pyrrolidin-2,5-dione, (3,5-di-tert-butyl-4-hydroxy-4-phenyl) -3-n-dodecyl-1-pyrrolidin-2,5-dione (3-tert-butyl-4-hydroxy-5-methyl-phenyl) -3-n-dodecyl-1-pyrrolidin-2,5-dione,   (3,5-di-tert-butyl-4-hydroxy-phenyl) -3-octa-   decyl-1-pyrrolidin-2,5-dione, (3,5-di-tert-butyl-4-hydroxy-phenyl) -3-phenyl-1-pyrrolidin-2,5-dione, 4-maleimido [(di-tert- butyl-3,5-hydroxy-4-phenyl-succinimido] -4-diphenylmethane, bis [(3,5-di-tert-butyl-4-hydroxy-4-phenyl) succinimido] -4 ', 4'-diphenylmethane, ( 3,5-dimethyl-4-hydroxy-phenyl) -3 (n-octadecyl-1-dioxo-2,5-pyrrolidin-3-yl) -3-n-octadecyl-1-pyrrolidin-2,5-dione and bis - [(di-tert) 3,5-butyl-4-hydroxy-phenyl) -3   2,5-dioxo-1-pyrrolidinyl-1,6 hexane. - 31 -   11. Composition containing organic matter   susceptible to degradation caused by oxidation, heat   their actinic radiation and a compound of formula I according to claim 1.   12. Composition according to claim 11, characterized in that the organic material is a synthetic polymer.   13. Composition according to claim 12,   characterized in that the synthetic polymer is a polyolefin   ne or a copolymer of an olefin.   14. Composition according to claim 12,   characterized in that the synthetic polymer is polystyrene   ne or a copolymer or terpolymer of styrene.   15. Application of compounds of formula I according to claim 1 to the stabilization of organic materials against degradation caused by oxidation, heat and actinic radiation.